The discovery of suspicious wires in plastic straws found in a toilet cubicle forced an aircraft flying to Spain to return to New York.
The Delta Airlines Boeing 767 with 206 people on board had been bound for Madrid.
Authorities said they searched the aircraft after its return but no bomb was found, the Guardian reports.
The aircraft landed safely at John F Kennedy airport shortly after 9.30pm local time, the airline said.
Delta described the situation as a "security concern" but gave no further details. Out of an "abundance of caution", the airline said in a statement, the plane turned around and returned to New York.
Police spokesman Paul Browne reportedly said two wires inside small plastic straws were found, one in the sink and one in the toilet.
Two passengers were questioned but neither was held. One was a woman from Argentina who reported trouble breathing around the time of the discovery. Also interviewed was a man believed to be the last person to use the bathroom before the wires were found. He denied any knowledge of the wires.